Incidence of Vocal Cord Paralysis in Medullary Thyroid Cancer

Medullary thyroid cancer (MTC) is a neuroendocrine tumor that comprises 3-5% of all thyroid cancers in the United States. Vocal cord paralysis (VCP) may be due to involvement of the recurrent laryngeal nerve (RLN) preoperatively, or nerve sacrifice during surgery. The purpose of this study was to demonstrate the incidence of VCP in MTC and evaluate whether VCP has an impact on overall survival.

This was a retrospective chart review of patients with MTC treated at Loyola University Medical Center from 2007 to 2021. Information on demographics, cancer diagnosis and treatment, laboratory data, and survival were collected.

A total of 79 patients were included in our study. 47 (59.5%) patients were female. The average age at the time of diagnosis was 51.3 years (SD 13.58). VCP was identified in 13 out of 79 (16.5%) patients. There were 71 patients with at least 1-year follow-up with median (Q1, Q3) years of 7.2 (3.9, 11.0). Those with VCP within 1 year had 7.2 (95% CI: 2.3, 22.7) times the risk of death compared to those without (p < 0.001).

MTC is a rare thyroid cancer, however, its incidence is on the rise. Our study suggests that the incidence of VCP in these patients appears to be higher than seen in other thyroid malignancies, and VCP is associated with a statistically significant negative impact on survival.

3 Laryngoscope, 133:890-894, 2023.